I. Field of the Invention
The present invention relates generally to a surgical implant and, more particularly, to an embroidered implant with resorbable flanges.
II. Discussion of the Prior Art
Various forms of disc replacement are in use, although historically the favored treatment particularly for a failed cervical disc has been disectomy followed by fusion, using a block or plug of bone inserted into the front of the disc space and abutting into the vertebrae above and below. This bone graft may or may not be stabilized using a plate fastened across the front of the disc space. Although fusion may relieve the symptoms for which the surgery was indicated, the loss in mobility of the particular spinal segment is undesirable, particularly in the cervical spine. The fusion of the disc segment also results in hypermobility of the motion segments above and below the fusion with increased strain on the adjacent discs, which can result in their accelerated degeneration, which will in turn require surgical intervention. Fusion using bone graft will have associated donor site morbidity if the bone is autograft or associated risks of infection if the bone is allograft. Alternatively, following the disectomy the disc space may be left empty, but this may lead to hypermobility problems at the operative level, kyphosis, spontaneous fusion and a loss in foraminal height.
Disc prostheses based on either articulating metal plates or metal end plates supporting a polyethylene spacer are in clinical use. Articulating devices reduce the loss in spinal mobility and the degeneration of adjacent discs. However, optimal positioning of the articulating disc prosthesis can sometimes prove challenging. The articulation also tends to be non-viscoelastic, with a fixed axis of rotation and can be under-constrained in axial rotation and distraction such that it does not truly emulate normal motion. As well as the general geometry mismatch, such prosthesis can also be adversely affected by the ingrowth of scar tissue.
The present invention is directed at overcoming, or at least improving upon, the disadvantages of the prior art.